The present application claims priority under 35 U.S.C. xc2xa7 119 of German Patent Application No. 198 48 810.6, filed on Oct. 22, 1998 and German Patent Application No. 199 44 704.7, filed on Sep. 17, 1999, the disclosures of which are expressly incorporated by reference herein in their entireties.
1. Field of the Invention
The present invention relates to a process for separating a running material web, e.g., a paper web, in which the material web is wound sequentially onto several winding cores, e.g., reel-spools, and initiating winding onto a new winding core each time a wound roll formed on a previous old winding core has reached a predetermined diameter. The new winding core is guided between a winding roll, e.g., a king roll, and the old winding core, which continues to be fed via the winding roll, and the running material web is cut or separated in a region between the wound roll formed on the old winding core and a nip formed by the winding roll and the new winding core.
The present invention further relates to a device for performing such a process with at least one cutting device.
2. Discussion of Background Information
Cutting (separation) processes and devices, such as those generally described above, are used in paper manufacturing, for example, to wind the finished paper web onto several winding cores, also referred to as reel-spools, one after the other without interrupting the manufacturing process, i.e., without turning off the paper machine.
In such a process, it must be ensured that the new web end, which is formed by cutting or separating the material web, is guided to the new winding core to form a new wound roll.
International Publication No. WO 97/48632, U.S. Pat. No. 5,360,179, and European Publication EP 0 658 504 B1 disclose cutting the paper web before the winding nip, which is formed between the winding roll and the new winding core, and providing either curved cutting lines or cutting lines that run diagonally to the direction of web travel. However, when the paper web is cut before the winding nip, there is a danger that the new web end will recoil and not be able to be guided into the winding nip.
Further, it has been disclosed to strike the paper web with a swinging separating device running along the width of the machine placed between the new and old winding cores, i.e., behind the winding nip. The ensuing cut edge that runs perpendicular to the direction of web travel can lead to problems in winding the new web end onto the new winding core.
Also, European Publication No. EP 0 658 504 B1 discloses separating the material web behind the winding nip, which is formed between the winding roll and the new winding core, but it is not mentioned how this occurs.
German Publication No. DE 44 01 804 A1 discloses moving a separating device, which includes a sectionally traversing knife as a separating mechanism, into the path of a paper web. It is further known from this publication to weaken the paper web only at one point with a knife and subsequently to separate it using pressurized air. However, using only the sectionally traversing knife or a knife that only weakens the paper web carries the danger of uncontrolled tearing of the paper web.
The present invention provides a process and a device of the type generally discussed above that allows an optimal initial winding of the new web end onto the new winding core.
Therefore, the invention provides for completely cutting (separating) the material web with at least one cutting device that is movable relative to the material web in a plane substantially parallel to the material web.
Moreover, the instant invention provides for cutting the material web in a vicinity of a winding roll, e.g., in a region between the winding roll and the wound roll or in a region upstream, relative to a web travel direction, from the winding roll.
Complete cutting or separation of the material web, according to the present invention, prevents an undefined tearing of the material web so that the leading edge of the new web end always has the same definable form. Moreover, the leading edge can be guided onto the new winding core in a defined manner. Further, the necessity of applying pressurized air to the material web for complete separation of the material web can be dispensed with.
According to an exemplary embodiment of the invention, the cutting device moves at an at least approximately constant speed and across, e.g., at least essentially perpendicular, to the direction of web travel.
In this manner, a cutting line can be produced in the material web that runs diagonally to the travel direction of the material web from one edge of the material web to its opposite edge. The diagonal edge of the new web end produced in this manner can be wound onto the new winding core in a relatively problem-free manner even under very high web speeds, and produces a conically wound initial winding.
According to a further embodiment of the invention, two cutting devices can be moved in opposite directions across, e.g., at least essentially perpendicular to, the direction of web travel and can preferably be moved at an at least approximately constant speed.
In relation to the cross-direction, the two cutting devices can be placed against the material web in the region of its center or its ends in such a way that two intersecting cutting lines ensue, both of which run diagonally to the web travel direction and either from the center to the edges or vice versa. In this manner, the leading edge of the new web end can be cut in a pointed fashion such that the initial winding onto the new winding core is simplified.
The present invention further provides a device for performing the process according to the instant invention, and includes at least one cutting device structured and arranged for completely separating the material web.
Accordingly, the present invention relates to a process for cutting a running material web in which the material web is wound onto several winding cores in succession, such that winding of the material web onto a new winding core begins after a predetermined diameter has been attained in a wound roll formed on an old winding core. The process includes moving the new winding core between a winding roll and the wound roll, such that the material web is fed onto the wound roll from the winding roll. The process further includes forming a nip between the new winding core and the winding roll, positioning at least one cutting device one of in a region between the wound roll and the nip and in a region upstream of the winding roll relative to a web run direction, and moving the at least one cutting device relative to the material web in a plane substantially parallel to the material web. In this manner, the running material web can be completely cut.
In accordance with another feature of the instant invention, the moving of the at least one cutting device may include moving the at least one cutting device across a web travel direction. In this manner, a diagonal cutting line results. The at least one cutting device can be moved substantially perpendicular to the web travel direction.
According to another feature of the invention, the moving of the at least one cutting device can include moving the at least one cutting device diagonally to a web travel direction. The diagonal movement can include a component parallel to and opposite the web travel direction. Alternatively, the diagonal movement can include a component parallel to and in the web travel direction.
In accordance with a further feature of the present invention, the moving of the at least one cutting device can include moving the at least one cutting device continuously across an entire width of the material web.
In accordance with another feature of the invention, the moving of the at least one cutting device may include moving the at least one cutting device at an at least approximately constant speed. The at least approximately constant speed can be between approximately 10 and 40 m/s.
According to another feature of the present invention, the process can further include accelerating the cutting device before cutting the material web.
According to still another feature of the invention, the at least one cutting device can include at least one of a knife, a rotating toothed cutting wheel, a laser, and a jet emitting a stream of water.
In accordance with a further feature of the present invention, the at least one cutting device may include at least two cutting devices, and the process can further include moving the at least two cutting devices in opposite directions across a web travel direction at an at least approximately constant speed. The at least two cutting devices can be moved substantially perpendicular to the web travel direction. Further, the at least two cutting devices can be located in positions separated in the web travel direction, and each of the at least two cutting devices can be approximately centered relative to a cross-wise direction. Moreover, the process can further include moving the at least two cutting devices from respective edges of the material web toward a middle of the web, or moving the at least two cutting devices from a middle of the material web toward respective edges of the web.
According to still another feature of the invention, the at least one cutting device may include at least two cutting devices, and the process can further include moving the at least two cutting devices relative to the material web in a plane that is substantially parallel to the material web.
According to a further feature of the present invention, the process may further include cutting the material web in a region of a free draw between the new winding core and the wound roll.
In accordance with another feature of the instant invention, the process may further include cutting the material web in a region in contact with the new winding core.
In accordance with a still further feature of the invention, during the cutting of the material web, the rotational axis of the new winding core can lie above a horizontal plane containing the rotational axis of the old winding core. Alternatively, during the cutting of the material web, the rotational axis of the new winding core can lie essentially in a horizontal plane containing the rotational axis of the old winding core.
According to a still further feature of the present invention, the cutting forms a new web end, and the process may further include applying the new web end to the new winding core. The applying of the new web end to the new winding core may include at least one of blowing, moistening, gluing, and providing strips of adhesive.
In accordance with another feature of the invention, the travel speed of the material web is not reduced during the cutting of the material web.
In accordance with a further feature of the instant invention, the new winding core may be inserted into the material web when the new winding core is moved between the winding roll and the wound roll.
According to still another feature of the invention, the material web can include a paper web, the winding cores may be composed of reel spools, and the winding roll can be composed of a king roll.
In accordance with yet another feature of the instant invention, the moving of the at least one cutting device may include moving the at least one cutting device across a web travel direction, whereby a diagonal cutting line results, and the moving of the at least one cutting device can include moving the at least one cutting device at an at least approximately constant speed. The at least one cutting device may include at least one of a knife, a rotating toothed cutting wheel, a laser, and a jet emitting a stream of water. Further, the at least one cutting device can include at least two cutting devices and the process may further include moving the at least two cutting devices in opposite directions during the cutting of the material web.
According to a further of the invention, the process can include cutting the paper web in a free run region between the wound roll and the new winding core.
According to another feature of the instant invention, the process can include cutting the paper web in a region between the wound roll and the nip.
In accordance with still another feature of the present invention, the process can further include cutting the paper web in a region upstream from the winding roll. Further, the process can include cutting the paper web while the paper web is in contact with a roll positioned upstream from the winding roll.
The present invention is also directed to an apparatus for cutting a running material web in which the material web is wound onto several winding cores in succession. The apparatus includes at least one cutting device adapted to completely cut the material web, and the at least one cutting device can be mounted for movement relative to the material web in a plane substantially parallel to the material web.
In accordance with another feature of the present invention, the at least one cutting device may be mounted for movement across an entire width of the material web.
In accordance with still another feature of the instant invention, a transport device having at least one cylinder/piston unit can be provided, and the piston can be coupled, on one end, to the at least one cutting device.
According to a further feature of the invention, a transport device having a continuous element can be arranged to wrap around deflection rolls, and the continuous element may be coupled, on an outer side, to the at least one cutting device. The continuous element can include one of a chain and strap.
According to a still further feature of the present invention, an old winding core on which a wound roll is being wound, and a new winding core on which a next wound roll will be wound can be provided. The winding cores may include an elastically deformable covering composed of a wear-resistant plastic. The wear-resistant plastic can include polyurethane.
In accordance with still another feature of the instant invention, an old winding core on which a wound roll is being wound, a new winding core on which a next wound roll will be wound, and a winding roll can be provided. The at least one cutting device may be located between the new winding core and the wound roll. The winding cores may include a covering made of metal, and the winding roll can include a covering composed of an elastically deformable wear-resistant plastic. The wear-resistant plastic can include polyurethane.
In accordance with a further feature of the invention, the at least one cutting device may be mounted for movement across a width of the material web. The at least one cutting device can include a jet adapted to direct a water stream at a new winding core.
According to another feature of the invention, the at least one cutting device can include at least two cutting devices, and the at least two cutting devices can be separated in the web travel direction and may be mounted for movement in opposite directions across the web travel direction. The at least two cutting devices may be mounted for movement substantially perpendicular to the web travel direction.
According to a still further feature of the instant invention, the at least one cutting device can include at least two cutting devices, and the at least two cutting devices may be mounted for movement relative to the material web in a plane substantially parallel to the material web. Each of the at least two cutting devices can be composed of at least one of a knife, a water jet, a laser, and a rotating toothed cutting wheel.
In accordance with another feature of the present invention, the at least one cutting device can include at least two cutting devices, and the at least two cutting devices may be mounted for movement in opposite directions. The at least two cutting devices can be mounted for movement from respective edges of the material web to a middle of the material web. Alternatively, the at least two cutting devices may be mounted for movement from a middle of the material web to respective edges of the material web.
According to yet another feature of the present invention, the at least one cutting device may be mounted for movement across a web travel direction, whereby a diagonal cutting line results, and the at least one cutting device can include at least one of a knife, a rotating toothed cutting wheel, a laser, and a jet emitting a stream of water. The at least one cutting device may be mounted for movement at an at least approximately constant speed. The at least one cutting device can include at least two cutting devices mounted for movement in opposite directions during the cutting of the material web.
According to another feature of the instant invention, the cutting device can include a fluid jet. Further, the fluid jet can include a stream of water.
In accordance with still another feature of the invention, an old winding core on which a wound roll is being wound, and a new winding core on which a next wound roll will be wound can be provided. The cutting device may be arranged between the old winding core and the new winding core.
In accordance with yet another feature of the invention, an old winding core on which a wound roll is being wound, and a new winding core on which a next wound roll will be wound can be provided. The cutting device may be arranged upstream, relative to a web run direction, from said new winding core. Further, at least one deflection roll may be located upstream from the new winding core. Still further, the cutting device may be arranged upstream from the at least one deflection roll.
Other exemplary embodiments and advantages of the present invention may be ascertained by reviewing the present disclosure and the accompanying drawings.